Dear Shasi,
Non-payment of wages /salary that too for a consecutive six months certainly shows the callousness of the employer towards the employee as well as his scanty regard for the laws of the land.
Besides, such an act is also a gross violation of the contract of employment on the part of the employer despite the reasons, if any he can cite against such a continuing lapse.
If your monthly gross salary is Rs.24, 000/= or less you can file claim u/s 15(1) of the Payment of Wages Act, 1936 before the authority under the Act who will normally be a Deputy Labor Commissioner for the area where the establishment is situated.
You can also add a prayer to order a penalty of 10 times of the claim amount.
You can file the claim directly or through the Inspector for the area or a trade union.
In case your monthly salary is more than Rs.24000/=, the avenue of a Civil Suit for the amount due as per the contract and damages for its breach is open to you.
Better decide and act immediately without any further loss of time.